The article is an attempt at applying a more abstract model of description of the slang lexicon. The authors examine a new word-formation model in the Bulgarian youth slang {\textendash} reverse transcoding. It constitutes a two-stage, two-way operation of formal loaning on the basis of a mechanical equalling of two lexemes from different languages. Reverse transcoding is viewed in correlation with the phenomenon of transposition. The authors investigate two of its mani- festations: hybrid transcoding and myxonymic transcoding. They explain them through synon- ymy by showing the process of their appearance and their functioning.